Is the spam ending up in the Junk folder? If it is then just hit the 'Not Junk' button. You can also run zmtrainsa manually against the users mailbox as 'ham', zmtrainsa from the command line will give you the format.

Solutions:
- raise the needed points for being reconginzed as spam from 6.6 to 7.x
- raise the negative value of BAYES_00 to smoething like -4
- check why all the blacklist filters apply and solve that problem